To Make PasteUsing a mortar and pestle, grind the toasted cumin seeds, coriander seeds and white peppercorns into a fine powder. Place in a bowl and set aside.With a mortar and pestle, roughly pound the green chillies and salt, then add in the Thai basil leaves and pound until fine. Add in some ground spice powder to absorb excess moisture.Add in the galangal, coriander roots, lemongrass and kaffir lime leaves, pound well.Throw in the chopped shallots, garlic and remaining dry spices and pound until it turns into a fine paste.Add in the shrimp paste and pound until well mixed.